The jumbled knot of loyalists arrived early at the U.S.S. Wisconsin, toting signs and chanting slogans as they trudged toward the ship’s wooden gangplank to catch a glimpse of Mitt Romney’s new No. 2. When the Republican nominee introduced Paul Ryan, a cheer went up from the spirited crowd. As he clambered up to the simple wooden podium to the theme from the movie Air Force One, Ryan paused to soak in the moment. “Wow,” he said, marveling as the audience applauded, the World War-era battleship named for his home state rising behind him under a gunmetal sky.

Which may have been the thought on everyone’s minds. Romney shook up the presidential race Saturday morning with a single stroke, tapping the architect of the Republican Party’s most audacious–and controversial–fiscal policies to fill out the GOP ticket. It was a chancy play by a cautious candidate, one that could infuse a nasty and tedious race with fresh life and new import.

It may also signify an overhaul of the Romney camp’s theory of the presidential race. For more than a year, Romney has framed the contest as a referendum on a failing president. Now he has made it a choice between two sharply different governing philosophies, and he touted his new running mate as “an intellectual leader of the Republican Party” with a distinct vision for the nation’s future. Ryan “has never been content to simply curse the darkness,” Romney said, speaking to a crowd of some 2,500 in this southern Virginia port city. “He’d rather light candles.”Ryan, 42, is a seven-term Congressman who represents a swing district in southern Wisconsin. He is the chair of the House Budget Committee, a perch from which he has played a pivotal role in shaping Republican policy on deficit reduction and entitlement reform. Ryan is best known for his “road map” for balancing the federal budget, which prescribes deep cuts to social programs. Ryan is a proponent of privatizing Social Security, turning Medicaid into a block-grant system administered by the states, and transforming Medicare into a voucher system to purchase private insurance. Though he cast a series of budget-busting votes during the Bush Administration – including for TARP, Medicare Part D, massive tax cuts and the Iraq War – Ryan’s meteoric rise within the party in recent years has been fueled by his reputation as a budget hawk who, like Romney, enjoys digging through data.

In some ways the similarities end there. The patrician GOP presidential nominee, 65, has chosen an earnest and youthful Catholic with Rust Belt appeal and an ability to articulate controversial policy in plainspoken language to middle class voters. The duo have dramatically different backgrounds. Romney has run as a corporate turnaround specialist who disdains Washington. Ryan has spent nearly his entire professional life in the capital, rising from Senate aide and think-tank staffer to one of the party’s intellectual figureheads. He is the first vice-presidential nominee to hail directly from the House in decades. And while he’s a familiar figure on the national stage — often elevated not by Republicans but rather Democrats, who have harnessed is budget blueprint for political benefit — he has no foreign policy or executive experience.

Supporters in Norfolk predicted the pick would energize fiscal hawks and Tea Party activists, many of whom harbor lingering suspicions about Romney but perceive in the selection a commitment to govern as a conservative. “It will unite conservatives, libertarians and others around this ticket,” says Marie Kessler, a Norfolk student lingering at the edges of the rally. Ryan, who had been urged by leading conservatives to leap into the race himself, is a favorite of party bigwigs and grassroots activists alike.

His selection invites an onslaught of attacks from Democrats, who have pounded Republicans over Ryan’s budget since it became the party’s blueprint. Obama himself has used Ryan as a foil throughout his administration, seizing on the Badger State Congressman’s budget to argue that the GOP’s fiscal policies disproportionately benefit the wealthy. “It is thinly veiled Social Darwinism,” Obama said of the Ryan budget plan in April. “It is antithetical to our entire history as a land of opportunity and upward mobility for everyone who’s willing to work for it – a place where prosperity doesn’t trickle down from the top, but grows outward from the middle class.”

Romney embraced Ryan’s budget during the Republican primaries. Now – perhaps knowing that he would be forced to defend the doctrine anyway — he has made it a central focus of the campaign, even if, as aides signaled, he does not intend to embrace every detail. Ryan, who has complained in the past about opponents who “demagogue” his positions, said in Norfolk that he welcomed a frank discussion about the nation’s future. “They are more worried about their next election than they are about the next generation,” Ryan said of Democrats. “We won’t duck the tough issues. We will lead. We won’t blame others. We will take responsibility. And we won’t replace our founding principles; we will reapply them. We will honor you, our fellow citizens, by giving you the right and opportunity to make the choice.”

Word of the pick broke late Friday night, just hours before Romney was set to kick off a a four-day bus tour through Virginia, North Carolina, Florida and Ohio, a quartet of battleground states that will determine the winner in November. His campaign formally confirmed the choice Saturday morning with press release announcing the second half of “America’s Comeback Team.” Almost immediately, the Obama campaign released a video labeling Ryan “the mastermind” behind the “extreme” Republican budget. “They’ll drag him through the mud. It’s going to come,” says David Jones, a Norfolk technical analyst who gushed about Ryan. “But they would have attacked anyone full force.”

That battle can wait; on Saturday morning, Republicans were brimming with enthusiasm. The modest but jubilant crowd of some 2,500 chanted Romney’s name as he took the stage, and broke into raucous cheers when he announced Ryan as his pick. Romney recovered quickly from an awkward moment when he mistakenly introduced Ryan as “the next president of the United States.”

“Every now and then I’ve been known to make a mistake,” Romney said, smiling. “I did not make a mistake with this guy.”